Filling structure for synthetic turf

ABSTRACT

“FILLING STRUCTURE FOR SYNTHETIC TURF” comprising artificial grass ( 1 ) provided with synthetic mat ( 2 ) from which filaments ( 3 ) protrude, being that under the synthetic mat ( 2 ) a filling layer ( 4 ), formed by sand and plant materials, such as rice husk, soybean hulls, coconut, sugar cane and bamboo fiber, is noted both in the form of fibers and/or grated, arranged between the filaments ( 4 ).

BACKGROUND OF THE INVENTION Field of the Invention

This invention patent application refers to a “FILLING STRUCTURE FOR SYNTHETIC TURF”, developed in order to provide a filling material easy to be acquired and of low cost with capacity to provide de artificial turf with appropriate elasticity and compaction characteristics, by using sand and plant materials such as rice husk, soybean hulls, coconut, sugar cane and bamboo fiber, both in the form of fibers and/or grated, to operate as filling material in an artificial turf structure, inserted with antifungal material.

Description of the Related Art

Between the 60s and 70s, a number of covered stadiums were built and, with this, the impossibility to receive the sunlight made the growth of natural turf impossible. The synthetic grass emerged, then, as a solution, having its use extended including outdoor stadiums. The first synthetic turf in history was installed in 1965 in the Astrodome stadium fields, in the USA, which received football and baseball games.

However, the products used to produce the grass resulted in a hard and uncomfortable surface for practicing sports. Players submitted to the synthetic turf disapproved its use, leading to a prohibition by the football regulatory associations. Until that, in the beginning of the 2000s, the development of the technology allowed the creation of a synthetic surface filled with sand and rubber in order to cushion falls and prevent slippages, favoring the practice of sports. Called “third generation of artificial grass”, it is considered as being as safe to the athletes as the natural grass. Thus, the synthetic grass has become more and more a feasible alternative to the natural grass, because:

-   -   It has increased durability, and the space where it is installed         for the Games can be used for other types of events, without         losing its quality;     -   It allows a more intensive and frequent use of the field;     -   It has lower maintenance costs, without specific care such as         irrigation, regular cut and use of pesticides and fertilizers;     -   It is very resistant to the weather effects;     -   Its maintenance does not require sunlight, adjusting itself,         therefore, to fields or covered places.

The textile materials have been widely used in the infrastructure for sports practices, particularly in the synthetic grass. The threads currently supplied by the market are made of polyethylene (PE) and polypropylene (PP).

Polypropylene (PP) is made of a plastic material, the fiber of which is “dryer”. It is a kind of cheaper fiber and with reasonable yield in the soccer fields. Polyethylene (PE), in its turn, contains a fiber consider as being “nobler”, with advanced formulation, the threads of which are soft and silky. Its aspect is very similar to that of the natural grass, it is less abrasive, it provides better appearance over the years and guarantees comfort and appropriate performance conditions to the athletes.

It is known that, in general, the artificial grasses, especially those intended for sports fields, as composed by a mat formed by a substrate on which filaments are vertically extended forming a green mantle; the filling materials are arranged between the filaments in such a way to form one or more filling layers; the most commonly used filling materials are sand and relatively elastic polymeric materials (primarily natural or synthetic rubber, but also a number of thermoplastic material types), which are mixed between each other or arranged in layers, according to the several methods.

Invention patents U.S. Pat. No. 4,735,825 and EP 174755 describe an artificial grass structure which includes a filling material comprising cork granules and peat-based materials, respectively.

PI 9810428-4, in its turn, addresses a synthetic turf for golf fields, tennis courts and other fields for the practice of games in grass surfaces, which is formed by a synthetic grass carpet presenting a flexible base layer (14) with plastic material threads in the form of vertical sheets strictly space between each other (12) forming a dense surface similar to grass. The carpet is supported over a lower damping lining (18), which is formed by a thick molded sheet made of expanded fillet polypropylene of open cells. The flexibly compressible lower polypropylene lining combined with the synthetic grass carpet similarly simulates the sensation of a surface intended for games covered with natural grass.

Patent PI 9810743-7 first comprised the provision of a fleece carpet coverage with a base sheet (14) which conducts vertical plastic threads strictly spaced between themselves similar to grass (12) forming simulated grass sheets. The coverage is placed over a flexible damping lining (18) supported over a firm surface, and the specific material similar to sand is blasted against the upper portions of the sheets (12) at sufficient pressure and for sufficient time to cut the upper end portions of the sheet in thin strips (23) which remain connected to their respective sheets and interlaced with the adjacent strips in order to form a dense belt over the upper surface of the carpet. During blasting, the flexible damping (18) below the carpet flexibly supports the vertical sheets, preventing them from being smashed or permanently compressed by the blasting force.

Patent MU 8203434-6, in its turn, is the type that is normally used in courts intended for sports practice or in areas with recreational purposes and which comprises a base (1) formed by a mesh or mantle (2) produced of appropriate material, such as, for example, polypropylene; base (1) is inserted by a number of filament (4) clumps (3) produced with an appropriate material, such as, for example, polyethylene; the clumps (3) cross the structure of the mentioned base (1) and are retained in it by applying a coating layer (5) which may use, for example, latex or other appropriate material, being that the enhancement proposed herein is essentially characterized by the fact that each clump (3) inserted in the base (1) which forms the concerned synthetic grass structure is formed by a grouping of filaments (4), where each filament 4 presents an essentially single-filament structure, the longitudinal structure of which is fully integrated and devoid of any type of longitudinal cut standard.

The fact is that the known filing materials are not fully satisfactory concerning a number of aspects, for example, in terms of performance, costs, draining capacity, maintenance of moisture, odor exhaled by the rubber which normally comprises recycled tires and increased temperature in the field.

SUMMARY OF THE INVENTION

The purpose of this invention application is to provide a “FILLING STRUCTURE FOR SYNTHETIC TURF” comprising a filling material easy to acquire and low cost able to provide the artificial turf with appropriate elasticity and compaction characteristics, and which allows good drainage, while guaranteeing an appropriate moisture level, decreased temperature, elimination of the odor in addition to low friction when in contact with the skin, especially developed for sports fields, in general, the invention refers to the use of sand and plant materials such as rice husk, soybean hulls, coconut, sugar cane and bamboo fiber, both in the form of fibers and/or grated, as a filling material in an artificial grass structure, optionally along with other components, particularly antifungal ones.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to obtain a perfect understanding of what was outlined above, illustrative drawings are appended, with numerical references along with a detailed description below, where:

FIG. 1 shows a schematic view of the turf.

DETAILED DESCRIPTION OF THE SEVERAL EMBODIMENTS

As inferred by the drawing and its details, we can note that the “FILLING STRUCTURE FOR SYNTHETIC TURF” comprised by artificial grass (1) provided with synthetic mat (2) from which filaments (3) protrude, being that under the synthetic mat (2) a filling layer (4), formed by sand and plant materials, such as rice husk, soybean hulls, coconut, sugar cane and bamboo fiber, is noted both in the form of fibers and/or grated, arranged between the filaments (3).

For being innovative and so far not understood in the state of the art, it perfectly fits into the criteria which define the invention patent. Its claims are as follows. 

What is claimed is:
 1. A “FILLING STRUCTURE FOR SYNTHETIC TURF” comprised by artificial grass (1) provided with synthetic mat (2) from which filaments (3) protrude, being that under the synthetic mat (2) a filling layer (4) can be noted, characterized by the filling layer (4) to be formed by sand and plant materials, such as rice husk, arranged between the filaments (3).
 2. The “FILLING STRUCTURE FOR SYNTHETIC TURF” according to claim 1, characterized by the fact that the filling material include one or more plant materials selected among soybean hulls, coconut, sugar cane and bamboo fiber, both in the form of fibers and/or grated, arranged between the filaments (3). 